Neuropeptides are chemical messengers whose function in the CNS remain unclear. The understanding of physiologic functions of neuropeptides would be greatly augmented by methods allowing sensitive, local analysis of multiple peptide systems over a significant time course. This information, taken together with data from classical (amine, amino acid) neuromodulator systems can provide critical information regarding interactive effects of chemical messengers acting at the DVC. Understanding peptide function and their interaction with aminergic systems provides the neurophysiologic template to understanding gastrointestinal pathologies related to cerebral systems (emotional agitation, cold exposure, surgery, trauma, sepsis, burns and functional bowel disorders), and could impact future therapeutic strategies. Future aims of the investigator include the application of the technology learned with the Pittsburgh groups to the study of conscious animal models, where behavioral influences may be studied. Implantations of chronic indwelling medullary recording arrays is routinely performed in an adjoining laboratory (Dr. Joe Travers-Ohio State). Adaptation of microdialysis technology to these elegant models is a research goal.